Gosh, never heard of a timing strip "falling out". Then, I found a youtube video where the person it happened too took a hammer to her printer. It didn't end well. In most cases it invloves considerable disassemby. They all attach differently and can be easily damaged. Given the TS3120's pricepoint, I'd replace the printer as the cost of service, shiping and/or repair will likely exceed its value. The exception would be if its under warranty. You can contact canon to review your options.
If your printer is still in it's 1 year warranty and you have a copy of the printers proof of purchase, please call Canon at 1-800-OK-CANON (1-800-652-2666), Monday - Friday, 8:00 AM - 8:00 PM EST excluding holidays. They can look into processing a warranty exchange for you.
If the printer is out of warranty, you qualify for the Canon Upgrade program.
This is for out of warranty units which have been diagnosed to require service or are incompatible with a new or upgraded system. This program allows you the opportunity to purchase a replacement product discounted from the list price. Free ground shipping is included with your purchase.
If you would like to take advantage of this offer, please call our Sales Department at (866) 443-8002 mon-Sat, 9 AM to 9pm EST. Let them know you have been working with technical support and that the Canon Upgrade Program was offered.